Various types of access doors for buildings are known in the prior art. Certainly, hinged doors are the most common variety, and such closure doors have been used in buildings since time immemorial.
Another type of closure door existent in the prior art is a door having a fixed panel and a sliding panel mounted for reciprocal lateral movement relative to the fixed panel. Such sliding doors are known as French doors. This type of sliding door is particularly utilizable in residential dwellings, and it is commonly used to provide egress to a deck, patio, etc.
Unique problems exist when such sliding doors are utilized in the construction of a home. It is, of course, important to deter water from entering into the interior of the home between the door panels. Additionally, particularly in very cold climates, it is virtually essential to provide structure for deterence of entry of exterior cold into the interior of the home.
The prior art has attempted various solutions to a number of the problems inherent with such doors. One attempted solution has been the placement of a pile dust block at a location under the sliding door panel. The placement of such a component does have the positive effect of inhibiting the entry of dust and other particulate materials into a location behind the sliding door. A significant problem, however, with sliding doors is the the entry of liquids (that is, rain, melted snow and ice, etc.). Such pile dust blocks, because of their nature, enable liquids to seep therethrough, and liquids, once they have passed through a dust block, can rise up over the track on which the slidable door panel moves, to cause damage or, at a minimum, inconvenience within the interior of the home.
It is to these dictates of the prior art and the problems discussed above that the present invention is directed. It is an improved sill construction which functions to better insulate the interior of a home in which a sliding door is installed from adverse external temperature and moisture conditions.